A DNS cache (sometimes called a DNS resolver cache) is a temporary database, maintained by a computer's operating system, that contains records of all the recent visits and attempted visits to websites and other internet domains. Your DNS cache stores the locations (IP addresses) of web servers that contain web pages that you have recently viewed. If the location of the webserver changes before the entry in your DNS cache updates, you can no longer access the site. In other words, a DNS cache is just a memory of recent DNS lookups that your computer can quickly refer to when it's trying to figure out how to load a website.
Does my phone use DNS?
To access websites on the Internet, your computer must leverage a DNS service, and it is usually configured by your ISP or your network administrator.
An Introduction to DNS Caching
To understand why you may need to flush your DNS cache, there are several components we need to break down. First, the Domain Name System (DNS) is an index of all the websites on the internet and their IP addresses. You can think of it as a directory or phone book for websites. As for ‘caching’, it’s the process of saving a snapshot of something (such as a web page) so it can be reloaded faster in the future.
So, DNS caching involves your Operating System (OS) or browser capturing recently-visited IP address and saving them in a database. This enables your browser to reload sites you’ve visited in the past more quickly than if it had to reference the DNS again each time. Unfortunately, your DNS cache may become corrupted, leading you into phishing schemes. It can also simply become outdated or create internet connectivity issues. In any of these situations, clearing your DNS cache can often help you resolve the problem and get back online.
Why Flushing DNS Cache?
- Troubleshooting connectivity issues.
- Troubleshooting and/or resolving DNS spoofing (e.g. DNS cache poisoning) issues.
- Resolving stale content issues (e.g. if a website has moved servers).
- DNS leak when using VPN (Virtual Private Network).
DNS Cache Flush
On a Windows computer, we can type ipconfig /flushdns at the command prompt screen. How to delete DNS Cache on an Android phone? The following methods allow you to remove old and inaccurate DNS information in Android phones.
- Open Google Chrome Web Browser.
- In the URL bar type in chrome://net-internals/#dns.
- In the left pane click DNS.
- In the right pane click Clear host cache.